Fix session resume and PSD container configuration

docker/core.Dockerfile

@@ -29,6 +29,7 @@ RUN ln -s /usr/local/lib/node_modules/npm/bin/npm-cli.js /usr/local/bin/npm \
 
 # Utente non-root
 RUN useradd --create-home --uid 10001 --shell /bin/bash thoth
+RUN mkdir -p /home/thoth/.pi/agent && chown -R thoth:thoth /home/thoth/.pi
 
 COPY harness/ /app/harness/
 # Pi scrive lock/settings in .pi: ownership thoth per sopravvivere al rebuild
@@ -43,8 +44,11 @@ RUN python -m venv /opt/venv \
     && /opt/venv/bin/pip install --no-cache-dir --upgrade pip \
     && (cd /app/harness && /opt/venv/bin/pip install --no-cache-dir .) \
     && cp /app/harness/workflow.yaml /opt/venv/lib/python3.12/site-packages/workflow.yaml
-# tht cerca config/tht.yaml relativo al CWD (ignora THT_CONFIG env). Symlink al workspace attivo.
-RUN mkdir -p /app/harness/config && ln -sf /app/harness/workspaces/local.yaml /app/harness/config/tht.yaml
+# Default locale e alias PSD convergono sul file canonico. Il CLI onora anche
+# THT_CONFIG, quindi cambiare CWD non cambia l'identita' dello workspace.
+RUN mkdir -p /app/harness/config \
+    && cp --remove-destination /app/harness/workspaces/local.yaml /app/harness/config/tht.yaml \
+    && ln -sfn /app/harness/config/tht.yaml /app/harness/workspaces/psd.yaml
 # PiProcessManager (backend) prepende harnessDir/.venv/bin al PATH del child Pi → symlink al venv reale
 RUN ln -s /opt/venv /app/harness/.venv